Manipulation means for controlling various electronic equipment such as an air conditioning apparatus are provided within a vehicle. A knob is a rotation type of input device that can be manipulated with a simple operation of grasping and rotating it, and is a representative manipulation means within a vehicle.
Research for applying a touch screen of a curved surface to electronic equipment that is mounted within a vehicle such as at a center fascia has been actively performed, and ongoing research for coupling a manipulation means such as a knob to the touch screen is also being actively undertaken.
Conventionally, a method of coupling an optical knob to a touch screen has been suggested. The optical knob includes a specific pattern rotating in conjunction with rotation of the knob at a rear surface of the knob, and a knob control system for a vehicle may recognize a control input from an image of the specific pattern. That is, as the optical knob rotates, a pattern of the rear surface of the knob rotates and thus a change occurs in a pattern image. Such a pattern change is converted to a rotation amount and rotating direction of the knob by the knob control system, and the knob control system may select a control input to correspond to the rotation amount and the rotating direction of the knob.
Such an optical knob does not require installation of separate wiring in order to transfer a control input according to a manipulation of the knob to a control system and may thus be easily coupled to touch screens of various designs, but erroneous pattern recognition occurs by light disturbance such as sunlight and thus there is a problem that a malfunction occurs.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.